A model has been developed to compare the system sharpness of continuous and discrete imaging systems. The continuous system consists of the traditional photographic process including the camera lens the film the printer lens and the photographic paper. The discrete system is an electronic still camera (ESC) and is built around a CCD imaging sensor and a laser printer the camera lens and the photographic paper are the same for both systems. The model uses CMT acutance to measure sharpness and introduces the concept of using the ratio of the aliased signal to the non-aliased signal as a measure of the probability of system aliasing. The model allows the user to study the trade offs between system sharpness and aliasing as a function of sensor resolution pixel size and the nature of the optical anti-aliasing pre-filter used in the ESC. The results of the model indicate that when a well-defined optical anti-aliasing pre-filter is made from a birefringent filter then when the pre-filter introduces a shift of about one-half the pixel pitch of the sensor then the potential for aliasing is minimized. For a given sensor resolution as the pixel size is reduced the potential for aliasing increases as does the system sharpness and when the potential for aliasing is minimized by use of the pre-filter the smaller pixel size still results in a greater potential for aliasing than for the pixels. For a given resolution it is possible to move from the Frame Transfer format to an Interline Transfer format and have the same system sharpness and potential for aliasing thus allowing flexibility in system design but the potential for aliasing is greater than the minimum value associated with the Frame Transfer format. As the system resolution increases the minimum in the potential for aliasing is more sharply defined as a function of the image shift introduced by the pre-filter. Also the potential for aliasing drops off sharply as the sensor resolution increases. In the case of the ESC system the number of lines used to form the final print can have a very large impact on the system sharpness and the amount of aliasing seen by the observer. 1.

As the final step in many electronic imaging or digital image processing investigations, a print quality study is used to determine the adequacy of the processing step in satisfying customer requirements with respect to quality. In general, the study takesthe form of a interaction between a group of judges and a selected set of images generated by alternative methods. It is a distinct challenge to interpret the data resulting from such an interaction and decide which method produces the highest quality output.

Sirke dre are very clear differences between analog (imp arid digital (non-impat) printed images there has been severe difficuky withdefining the quality ofdigital images in analog terms. The three optical tharteristIcs which fine digital to images are: edge acuiiy density J shape factor which edge is the most significart. 11 method ofpIying a scale of" lines r centimeter (inch)" common in analog image tectuiology will not work with dgital image chnsques. Examinion and statistical survey of over 3 toner-output pages from a varty of dIgital electronic printing cliiohgis ty means of SEM microspectrophotometry and optical microscopic analyses indicated a urse tharristic concerning the edge uity. 11 " spreaf or " satelliting" of the tonor defined a ictaIjIe patm in etch case. ''flk difference or ''ra between th edges of the addressed (electrophotographie or ekctrogr letter form and the actual resolved (tonered) edges can be quantified. This da was used as the basis of a serrs of micro-optical comparors for fining aii measuring the separation between the two edges (*kessable) as (resolvthle) preely. 11 results constitute not only a precise method of measuring edge acuity but a possible standard which may be applied to all electronic printing tectuiologies. I. ANALOG AND DIGITAL IMAGES COMPARED. The specific differences in optical characteristics between analog (Inpact) printed images and digital (non-impact) priiied isnages can be seen ii the companion in Illuatrationi 1 and 2. In

Image processing operations may be performed in either the spatial domain or the frequency domain. Spatial domain image processing is attractive because it avoids the mathematical transformations required by frequency domain processing is computationally more efficient and is more intuitive. Historically spatial processing has been done by traversing the image in strict raster-scan fashion (left-to-right top-to-bottom a paradigm encouraged by the syntax of traditional Fortran-like programming languages. Cellular logic is a different way of thinking about spatial processing in which images are modified h defining a set of logical operations to be performed on small groups of pixels neighboring any general pixel in the image. The same operations are then performed on every pixel in the image " all at once" there is no implied ordering in the processing ofthe pixels. This means that cellular logic has a natural parallelism making it easy to implement on parallel computers. Cellular logic is also efficient even on single-processor machines. since pixels are processed in machine-word sized groups. Another interesting property of cellular logic is that it is Turing-complete: in other words it has the same computational power as any programming language in general so that arbitrarily complex operations may be constructed from a small number of simple logical primitives. In addition the bit-block transfer instruction (bitbit) offers a convenient means of implementing cellular logic functions in software. As its name implies bitbit transfers

Chain codes are widely nsed for representing a line drawing digitally using connected short line segments. When the encoded image is presented in the usual way, the resolution is constrained by the grid size. Here we consider using a linear smoothing filter for improving the reconstruction accuracy. The linear reconstruction filter that minimizes the meansquare reconstruction error is derived, and it is found that subpixel accuracy can be achieved by using such a filter.

. Dimension Technologies has developed a black and white 640 X 480 pixel flat panel autostereoscopic computer monitor that interfaces with the IBM PC family of comouters and most comoatibles. A Mac version is under develooment. The monitor emDloys a iiauid crystal dlsDlay as the ''mage generatng element. The LCD s used in combination with a patented illumination system to or-oduce vivid stereoscooic images that can be seen by several observers from several locations in front of the screen. This oaoer describes the monitor and how it works. the advantages of DT s autostereoscoic technology. and the results achieved wth the monitor as a disoiav for comDuter-qenerated maqe and still television images at DT and at customer stes. Aications for stereo dislavs are reviewed. New develoornents are also described. 1.

The theory design and performance of a fast precision flying spot laser scanner position detector are described. Using Fourier analysis a sampling requirement has been derived that assures sufficient information is contained in the samples of the flying spot profile for accurate calculation of its centroid. The derivation shows that for accurate geometric moment determination sampling can be done at a rate lower than that required by the Whittaker-Shannon sampling theorem which applies to complete reconstruction ofthe distribution. A formula for the calculation of moments from the samples is given. A numerical analysis is performed to quantify the accuracy of the calculated first moment for non-ideal sampling conditions. The theory is applied to a laser beam position detector taking into account the irradiance profile the sampling aperture the number of samples required quantization and noise. The predicted performance is compared with experimental results. 1.

In order to study the humidity dependence of thin film ceramic substrate electroluminescent devices two devices were made using thermal evaporation -- one with a slightly smaller average grain size in the active layer than the other. The devices were exposed to various levels of relative humidity and were electrically characterized using charge-voltage measurements. It was found that the presence of water in the active layer decreased the leakage resistance of the device while it increased the capacitance of the active layer. The changes observed in the active layer were not fully reversible. 2.

The Center for Optics Manufacturing, located at the University of Rochester's Institute of Optics, is a collaborative effort with industry, several academic institutions and the Department of Defense. The Center's mission is to develop advanced optics manufacturing technology, implement technology transfer, and establish training and education for the optics industry. Areas of technology include materials, processes, quality, equipment, metrology and management. A principal objective is to research and introduce innovative technology and novel techniques that increase the competitiveness of the optics manufacturing base and its customers. The Center (COM) is designed to promote cooperative industry-university-government interaction in areas of unique potential for translation into industrial growth. This interaction is directly beneficial in identifying and adopting emerging technology. COM encourages the participation of manufacturers, prime contractors and government agencies by offering training, information and technology. COM user labs, which demonstrate newly developed technology and methods, will provide unique facilities and equipment that benefit all participants. This university-industrygovernment collaborative effort will identify results that lead to the development and commercialization of new products, new manufacturing technology and serve as the central resource for optics technology advancement. While the Center's primary location is at the University of Rochester, the COM has a national academic and industrial constituency. The Universities of Arizona and Central Florida will establish Regional Centers located close to major optics centers. This maximizes interaction and support of the industrial base. These activities will influence educational programs at the academic institutions and the transfer of technology to participating industry and government organizations. Other universities and national laboratories have offered resources and will add valuable contributions.

The Polarization Phase Sensor (PPS) is a white light polarization shearing interferometer which has successfully demonstrated absolute mirror segment alignment in the RADC/OCSE Optical Systems Engineering Laboratory. Operating at the center of curvature the PPS demonstration has been configured to perform closed-loop phasing of a three segment spherical mirror. The PPS may be adapted for use with other optical systems including aspheric surfaces. PPS device simulation and testing have verified this. This paper will address the optical layout of the device experimental testing and the results of subsequent analysis. 1.

Simultaneous absorption of two red photons from a strongly focused subpicosecond colliding pulse mode4ocked dye laser stimulates visible fluorescence emission from fluorophores having their normal absorption in the ultraviolet1. The quadratic increase of the two-photon excitation rate with excitation intensity restricts fluorescence emission to the focal volume thus providing the same depth resolution as does confocal microscopy. Image degradation due to out of focus backround is thus avoided. Photobleaching and most cellular photodamage are similarly confined to the focus thereby minimizing sample degredation during acquisition of the multiple sections required for 3-d image reconstruction. Fluorescence images of living cells and other thick photolabile fluorescence labled assemblies illustrate the depth discrimination of both two-photon fluorescence excitation and photobleaching. The quadratic intensity dependence of two-photon excitation allows 3-d spatially resolved photochemistry in particular the photolytic release of caged compounds such as neurotransmitters nucleotides fluorescent dyes and second messengers such as 1P3 and Ca. The two-photon release of cased ATP has been measured and release of a caged fluorescent dye has been shown. Point photobleaching and a 3-d " write once read many" optical memory have been demonstrated. Two-photon excitation of photo-initiated polymerization with a sharply focused single beam allows microfabrication of complex structures of arbitrary form. By scanning the focused beam through a liquid polymer with a UV excited initiator it is possible to harden the polymer only at the focus thereby creating

High quality molded optical components and strict optomechanical tolerances have led to a new class of barcode scanner. Dynamic analysis of the scanning system and diffraction analysis of the thru focus laser spots are used to optimize the design. The outcome of this analysis is presented herein. 2 . 0

Artifacts due to patient motion in the slice-selection direction (Z motion) have been a major source of MR image degradation for many years but have not been addressed as much as in-plane motion due to the complexity of modeling and correcting for the motion. In this paper we present a model and a detection and correction scheme for amplitude aberrations due to motion in the slice-selection direction. 1.

A correlation exists between chromosome breakage and radiation exposure so that counting chromosome fragments can provide a measure of the radiation dose to an organism. We describe our method for automatically counting prematurely condensed chromosome fragments from microscope images of the exploded nucleus. An alternative perhaps more promising non-imaging approach using flow karyotyping is also discussed. 1 .

We have investigated the processes involved in cutting biological tissues with surgical sapphire tips metal tips and sculpted quartz fibers. We have found that all of these devices make very inefficient use of expensive laser energy. We have further found that the cutting actions of all the tips tested rely primarily on the concept of " hot" tips operating at temperatures of 600C to 700C. The heat transfer between tip and tissue is primarily via blackbody radiation from the tip. The process is aided by the coincidence of the peak of the blackbody radiation spectrum for 600C to 700C at -3 im with the very strong water absorption peak at the same wavelength. Based on the " hot" tip concept the efficiency of these tips can be increased from the present 1 to 3 to near 100. The resulting reduced laser power requirements allow contemplation of diode laser sources with concomitant savings in complexity power and cooling requirements maintenance and lifetime improvements and significant cost savings. 1.

Cardiac cells exhibit rhythmic contractions when electrically paced and maintain striation patterns throughout the contraction-relaxation cycle similar to one-dimensional diffraction grating that changes in spatial frequency. The current study demonstrates the application of an on-line hybrid optical-digital processor with liquid crystal television (LCTV) acting as a spatial light modulator(SLM) to monitor the dynamics of contraction of single cardiac cells in real-time . The processor which is interfaced with a phase contrast microscope performs the Fourier transformation of the cell''s striated image optically and records the Fourier spectra digitally using a charge coupled device (CCD) camera. A series of digitized images of the Fourier spectra each of duration of 16 . 67 msec (non-interlaced frames) is captured during one contraction cycle (''4000 msec). The sarcomere length at each time point and contraction velocities are calculated. The overall system is initially calibrated using a high-resolution Ealing target. Experimental results demonstrate the improvement of contrast by about 300 using the LCTV and the optical-digital processor can faithfully track sarcomere mechanics. 1 .

In the past decade a broad range of sensing applications have been reported which utilize optical fiber based sensors. 1''2 These applications range from the measurement of a variety of physical parameters to the quantitative determination of chemical and biochemical species. This paper discusses recent work performed at Eastman Kodak CoiTpany concerning development and testing of fiberoptic sensors in process monitoring and control environments. Topics include sensing mechanisms sensor design environmental considerations and sensor performance characterization in process environments. Sensing mechanisms described inlude optical time domain reflectometer (OTDR) distributed fiber-optic sensing multiplexable reflective fiberpair sensing and photoncorrelation spectroscopy. Distributed fiber-optic sensing applications including temperature pressure strain humidity chemicals and distributed alarms are discussed. Reflective fiberpair sensors described include edge location distance and vibration. Use of photoncorrelation techniques with fiberoptic sensors are also described and process applications of these techniques are presented. 1.

An interferometric fiber optic sensor using ordinary single-mode fibers is developed to detect elastic strain waves for nondestructive evaluation of composite materials. This fiber sensor has been embedded in both graphite/epoxy and Kevlar/epoxy composite specimens. Applications of the sensor for detection of acoustic emission and laser generated ultrasound are presented. Limitations of the sensor are also discussed. 1.

Fiber optic gyroscope (FOG) technology has reached fruition as a marketable instrument. Bell Aerospace Textron and Standard Electrik Lorenz offer a line of FOGs from standard to enhanced performance designs. Operation of these FOGs is based on an interchangeable and reliable interferometric optics unit with electronics tailored to meet customer needs. Attitude Reference and Heading stabilization and rate applications are the market targets for this line of gyroscopes. They are marketed with the competitive edge of reduced life cycle and maintenance costs. We will show how the core optics unit is reliably made and applicable to the range of applications being considered. Specifically the ability to use the same set of optics for various design will be detailed along with the digital method of retrieving sensor data. Outputs are available as either rate or angle and analog or digital allowing implementation by customers in existing equipment without large accommodating changes in the surrounding system. Performance specifications will be presented for the standard and enhanced FOGs and test data from Bell Aerospace Textron Standard Electrik Lorenz and National Laboratories will be presented verifying the operational performance capabilities of the open loop version of the FOG. Extensive testing of the FOG has been conducted over a large environmental regime including temperature variations magnetic field intensities vibration and shock. Specific drift scale factor misalignment angle and unique vibration tests will be described and test

A fiber optic position sensor utilizing visible light sources microprocessor and a selective absorption/reflection technique is presented as a replacement for conventional limit sensing technology including more recently developed opaque shutter-type limit switches. Because the technique to be presented applies the ratio of inversely varying returned light signals as a criterion for switching it is highly tolerant of losses induced by variability in cable length termination quality and microbending. In addition because both light signals are modulated by the sensor the operational state of the sensor is monitored. A sensor of this type using visible light sources plastic fiber and microprocessor circuitry has been built. The sensor has been commercialized and has found application in the cosmetics industry. The sensing technique is covered by a U. S. Patent. The theory of the sensing technique will be presented. A liquid level sensing application which exploits the loss tolerant self-monitoring nature of the sensor will be discussed. This application induces switch actuation via pressure change in a dip tube. It offers advantages of the ability to sense a wide range of liquid viscosity and immunity to coating buildup effects.

Since the first practical laser was developed in the 1960''s the medical community has pursued the application of lasers for medical surgery. Unlike industrial laser applications where the laser can be positioned directly in front of a desired work area medical systems have the need to remotely channel the laser to the operation site. Silica-core optical fibers have become a standard vehicle for this purpose because of their availability and low cost high laser damage threshold biocompatibility high strength and reliability. Much of the fiber technology available today is the result of extensive development associated with telecommunications.

The Pockels Effect has been demonstrated in thermally evaporated polycrystalline thin films of ZnS. The strongly till] oiented films were found to have an electro-optic constant of r413 rn/V for fields perpendicular to the [111] plane. 2 .

Optically powered conventional instrumentation with optical fibre links combines advantages of a familiar technology and that of fibre optics. For safety and cost effectiveness considerations reducing power consumption of the optically operated conventional instrumentation is important. Development of conventional pressure sensors and actuators to suit low-power operation is presented. Power budget of optically activated instrumentation systems is discussed. 1.

A laboratory sized X-ray projection microscope and microtomographic imaging system is being developed at SUNYAB (AMIL-ARTS). High resolution two dimensional images can be recorded rapidly using a high resolution phosphor and a cooled slow scan CCD camera. The effective source size is kept small to maximize the resolution. For this purpose the electron beam is focused onto a thin film target. Three dimensional information can be derived from the high resolution two dimensional images by generating stereo pairs or by reconstructing the complete tomographic image. Real time stereo pairs can be produced by rapidly moving the position of the electron spot between two locations on the thin film target thus irradiating the specimen with X-rays from two spatially distinct directions. For high resolution tomography or microtomography the two dimensional images are recorded for a large number of different orientations of the specimen. A cone beam reconstruction scheme based on a convolution and back projection algorithm is being developed. To optimize the experimental parameters in microtomography a variety of mathematical phantoms have been examined using computer simulation technique. The experimental results reveal the quantitative relationship between the accuracy of the reconstructed image and the experimental parameters such as object shape orientation and position. 1.

An experiment occurring in an orbiting platform examines the mass transfer across gas-liquid and liquid-liquid interfaces. It employs an imaging system with real time image analysis. The design includes optical design imager selection and integration positioner control image recording software development for processing and interfaces to telemetry. It addresses the constraints of weight volume and electric power associated with placing the experiment in the Space Shuttle cargo bay. Challenging elements of the design are Imaging and recording of a 200 micron diameter bubble with a resolution of 2 microns to serve as a primary source of data Varying frame rates from 500 per second to 1 frame per second depending on the experiment phase Providing three dimensional information to determine the shape of the bubble. 1.

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Journal of Applied Remote SensingJournal of Astronomical Telescopes Instruments and SystemsJournal of Biomedical OpticsJournal of Electronic ImagingJournal of Medical ImagingJournal of Micro/Nanolithography, MEMS, and MOEMSJournal of NanophotonicsJournal of Photonics for EnergyNeurophotonicsOptical EngineeringSPIE Reviews